Bolt-anchor.



um TED sTATEs PATENT oEEic JOSEPH KENNEDY, OF NEN YORK, N. Y., ASSIGNORTO THE CLEMENTE COMPANY, A CORPORATION OF NEW YORK.

BOLT-ANCHOR.

Application filed August 14, 1913.

To (Illu/710m it may Concern Be it known that I, JosErH KENNEDY, a.citizen of the United States, and a resident of New York, county of NewYork, and State of New York, have invented certain new and usefulImprovements in Bolt- Anchors, of which the following is aspecification, reference being had to the accompanying drawings, forminga part thereof.

My invention relates to bolt anchors and more particularly those of theexpansible type and its object is to provide a simple and inexpensivedevice which may be used in walls of concrete or other material, to forma durable and effective hold for the threads of a bolt.

In order that my invention may be thoroughly understood, I will describemy invention in the following specification and then point out the novelfeatures thereof in appended claims.

Referring to the drawings: Figure 1 is a sectional longitudinalelevation of a simple form of expansion bolt made according to thepresent invention. Fig. 9. is a transverse 'section taken on the line2-2 of Fig. l. A

modification of the form of the bore of the device of these figures isshown in transverse elevation in Fig. 3. A somewhat similar expansionbolt is shown in longitudinal section and end elevation in Figs. 4 andrespectively, with a modified form of the outside of the device shown inend elevation in Fig. 6. Another modification of structure isillustrated in longitudinal elevation partly in section and intransverse section ln Figs. 'T and S respectively.

Like characters of reference designate corresponding parts in all thefigures.

In all of the drawings the bolt anchor comprises a hollow shell 10 whichis split lengthwise so that it may expand when abolt is screwed into it.This may be accomplis-hed by a single slit such as 11 in Figs. 1 1nd 2which extends throughout the length of the shell, or by a plurality vofsuch slits such as shown at 12 and 13 in 3 for example, which divide'the shell into a. plurality of segmental parts. It is not necessarythat these slits be on straight lines parallel with the axis of theshell for they may if desired be on helical lines as at 14:, Fig. t.

The inside of the shell is provided with neans for receiving the threadsof a bolt Specication Aof Letters Patent.

Patented June (i, 1916.

Serial No. 784,8?4.

20 of soft metal projecting into the bore into .y

which the inserted bolt may cut its own threads. rIhe ends of these lugslie in an imaginary surface, the cross-section of which is elliptical orother form of non-uniform diameter, the maximum diameter being at theslit 1l and being but slightly greater than the diameter of the boltwhich is to be used with the device.

A slight modification of the bore of the shell is shown in transversesection in Fig. 8, in which the ends of the lugs lie in surfaces thesections of which are the sides of a flattened polygon. v

This device is used by drilling a hole in the wall, ioor or otherstructure of such material as will not readily receive the threads of abolt., embedding the device in the hole and then inserting the boltwhich, while it cuts its own thread in the lugs 9,0, forces the shellapart o-r expands it so that its outer surface is' forced against thesurface of the hole in which it is inserted.

In order to oppose any tendency of the shell to rotate in the hole whenthe bolt is being screwed in, the outside of the shell may be made ovalas is shown in Fig. 3. Or it may be provided with outwardly projectingribs which may be interrupted as at 2l in Figs. 1 and l.' rI`he ends ofthese projecting ribs may lie in an imaginary surt face elliptical incross section as in Figs. 2 and 5, or the cross-section of which is inthe form of a flattened polygon as in Figs. 3 and 6. In both of thesearrangements the shorter ribs are on the surfaces of the shell' whichare moved away from each other when it is expanded.

The form of my invention shown in Figs. 4, 5V and 6 is internallythreaded, as at 15.

V'Vhenthis construction is used it is desirable to have the threadedbore taper inwardly Vtoward the inner end o-f the shell.

It is not necessary that the projecting ribs be parallel with the axisof the shell and in Figs.4 7 and 8 I have shown the shell prolll hen theholes in which bolt anchors of this general character are to be used,are drilled by hand, the outer ends of the holes are usually larger thanthe rest of it. For this reason it is often desirable to flare theoutei` end of the shell. This construction causes the shell to centerits outer end in the hole and also causes it to more completely lill theouter end of the hole and thus present a more finished appearance. lnFig. 7 the structure shown has both the shell itself flared and the ribs2l made higher near the outer end of the shell.

The arrangement of projections set forth and described is such as toproduce the best results.

Short projections are near the line of division between parts where theydo not prevent the spreading of the parts, but do hold to some extentowing to the `granular surface of the hole. 'lhey are primarily intendedto hold the anchor in the center of the hole. The longer projections,which are located between the lines of division and eX- tend beyond animaginary cylindrical surface corresponding to the hole, are adapted tobe somewhat collapsed when the anchor is driven into the wall, butbefore they are collapsed and while they are being collapsed they cutinto the wall so that when the anchor is ready for the bolt, it is heldin the wall with considerable security, enough at least to preventrotation of the anchor. The insertion of the bolt then spreads the pairsto complete the grip and during this operation, the short projections,as already eX- plained7 hold the anchor in the center of the hole.

The irregular or helical division line between the parts of the anchoreectively prevents longitudinal displacement of the two parts andrenders the use of interlocking projections or other means foraccomplishing` his purpose unnecessary.

In this application several different struetures which embody myinvention are illustrated and described. This is to show that l intendno other limitations than those in the appended claims as the inventionmay be utilized in structures of widely different form and design.

lVhat l claim is:

l. An expansion bolt comprising a hollow slitted shell, projections fromthe surface thereof, the ends of said projections lying in an imaginarysurface, the cross-section of which is a geometrical ligure having asmaller dimension across the plane in which the shell is slitted than ithas in the direction at right angles thereto.

2. A bolt anchor comprising a hollow slitted shell, means within saidshell for re ceiving the threads of a bolt, and holding membersprojecting from the outer surface of the shell in such a manner that aline drawn through the outer ends of said projecting members is nearerthe center of the shell at two diametrically opposed points than it isat two similar points midway between the aforesaid points.

3. A bolt anchor comprising a two-part hollow shell separated alongdiametrically opposed lines, .means within the shell for receiving thethreads of a bolt, and holding members projecting from the outer surfaceof the shell in such a manner that the ends of said members near thelines between the parts of the shell are carer the central axis of theshell than are the ends of the holding members between said lines ofseparation of the parts of the shell.

4. A bolt anchoicomprising a two-part hollow shell separated along`diametrically opposed lines, means within the shell for receiving thethreads of a bolt, and holding members projecting from the outer surfaceof the shell in such a manner that the ends of said members are in animaginary surface, the cross-section of which is a curve of non-uniformdiameter with the shortest diameter thereof near the lines of separationof the shell.

5. A bolt anchor comprising a two-part hollow shell separated alongdiametrically opposed lines, means within the shell for receiving thethreads of a bolt, holding members projecting from the outer surface ofthe shell unequal distances from the axis of the shell with theirmaximum distance of projection from said axis intermediate the lines ofseparation of the shell.

6. A bolt anchor comprising a two-part hollow cylindrical shell. of hardmetal separated along diametrically opposed lines, screw-threads formedin both of said parts converging toward the inner' end of the shell,holding members projecting from the outer surface of the shell unequaldistances from the surface of the shell with their maximum distance ofprojection from said surface intermediate the lines of separation of theshell.

7. An expansion bolt comprising a hollow shell longitudinally dividedalongl diametrically opposed helical lines.

8. An expansion bolt comprising a hollow shell longitudinally dividedalong helical lines.

ln testimony whereof, I have hereunto set my hand in the presence of twosubscribing witnesses this 11th day of August, 1913.

JOSEPH. KENNEDY.

Witnesses I. B. MOORE, EDNA ZINMAN.

copies of this patent may be obtained for ve cents each, by addressingthe Commissioner @t Patents Washington, D. e.

